ARM: s3c24xx: ts: document function argument

Document function argument in kerneldoc comment to fix W=1 compile
warning:

    arch/arm/mach-s3c24xx/setup-ts.c:27: warning: Function parameter or member 'dev' not described in 's3c24xx_ts_cfg_gpio'
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

arch/arm/mach-s3c24xx/setup-ts.c

@@ -18,6 +18,7 @@ struct platform_device; /* don't need the contents */
 
 /**
  * s3c24xx_ts_cfg_gpio - configure gpio for s3c2410 systems
+ * @dev: Device to configure GPIO for (ignored)
  *
  * Configure the GPIO for the S3C2410 system, where we have external FETs
  * connected to the device (later systems such as the S3C2440 integrate